Full Notification

The U.S. Army Corps of Engineers, Omaha District, in partnership with Union County, South Dakota, will host a public open house for the Lower Big Sioux River Flood Risk Management Feasibility Study on Thursday, October 22, 2026, from 6:00-7:00 p.m. at the North Sioux City Community Hall, 205 Sodrac Drive, North Sioux City, South Dakota.

The feasibility study is in its early stages, and no construction project or flood risk management measure has been selected or approved. USACE and Union County are beginning the process of evaluating existing flood risks along the lower Big Sioux River and identifying potential opportunities to reduce those risks.

The open house is intended to introduce the study to the community, explain the feasibility study process, and provide an opportunity for the public to ask initial questions and speak directly with members of the study team.

Open House Format

The meeting will be conducted in an informal, open house format rather than as a formal presentation. Attendees may arrive anytime between 6:00 and 7:00 p.m. Technical staff from USACE and its partners will be available for one-on-one discussion. Informational displays will also be available showing the study area, anticipated study schedule, and general feasibility study process.

Background

The study area includes communities along the lower Big Sioux River in southeastern South Dakota and northwestern Iowa. The study will examine existing flood risks and consider a range of potential measures that could help reduce those risks. Potential measures will be evaluated and refined as the study progresses to determine whether there is a federal interest in recommending a flood risk management project.

Public Participation

Community involvement will be an important part of the study as it moves forward. This initial open house provides an opportunity for residents, property owners, businesses, and other interested members of the public to learn about the study early in the process, ask questions, and share information with the study team.

Additional opportunities for public involvement will occur as the study progresses and potential measures are identified and evaluated.

Meeting information

Thursday, October 22, 2026

6:00 – 7:00 p.m.

North Sioux City Community Hall

205 Sodrac Drive

North Sioux City, SD

For additional information about the Lower Big Sioux River Flood Risk Management Feasibility Study, please visit: https://www.nwo.usace.army.mil/Missions/Civil-Works/Planning/Planning-Projects/Lower-Big-Sioux-River-Flood-Risk-Management-Study/

Questions and comments about the Lower Big Sioux River Flood Risk Management Feasibility Study may be submitted to [email protected].

Release no. 26-020